Bake-oven.



Patented February 28, 1905.,

PATENT Urrrcn.

ALPHONSO EDWVARDS. OF RE'DLANDS, CALIFORNIA.

BAKE-"OVEN.

SPECIFICATION forming part of Letters Patent No. 783,689, dated February 28, 1905.

' Application filed October 13, 1903. Serial No. 176,831.

To all '11/71/0112/ it may concern/.-

Be it known that .I, ALruoNso Enwanos. a citizen of the United States. residing at Redlands, in the county of San Bernardino and State of California, have invented new and useful Improvements in Bake-Ovens, of which the following is a specification.

This invention relates to bake-ovens, and more particularly to the class known as in side ovens, wherein the lire is laid inside the oven itself in contradistinction to outside ovens, wherein a furnace is provided at one side of the oven proper. My improved oven may, however, be used as an outside oven, if desired.

The primary object of this invention is to save and utilize as far as possible the heat that is ordinarily wasted in inside ovens. The usual practice is to provide an oven or chamher of refractory material wherein a lire is lighted and maintained until the oven has be come sul'liciently heated, the lire being then drawn and the material to be baked placed in the oven, which is then kept closed until the baking is completed. In this operation the products of combustion pass directly up into the chimney and a large part of the heat of combustion is thereby wasted.

My invention provides means for more fully withdrawing the heat from the products of combustion and retaining the same in the walls and floors of the bake-oven. I

A. further object of my invention is to provide for a more uniform heating of the bakeoven.

Further objects of the invention will appear in and from the aceon'ipanying description and claim.

The accompanying drawings illustrate the invention. I

Figure I is a front elevation of a bake-oven constructed according to my invention. Fig. II is a longitudinal section thereof on the line II II in Fig. I. Fig. III is a horizontal section on the line III III in Fig. II. Fig. IV is a horizontal section on the line IV IV in Fig. II. Figs. V and VI are detail vertical sections on lines V V and VI VI in Fig. III. Figs. VII and VIII are detail horizontal sections showing different forms of heatii'ig devices in the air-inlet passages.

The oven is constructed of brick or other suitable n'lasonry or material with side walls 1 1, front and rear walls 2 3, and roof or top 4. A bed or door 5 extends the whole length and width of the oven at a suflicient distance below the top 4C to provide a chamber 6, which serves as a baking chamber or oven proper. The bed or floor 5 is formed of any suitable material, such as grouting or concrete, containing lrmgitudinal passages 7, serving as return-passages. The u ppcr chamber (3 is provided at its forward end with a door 8, through which the material to be baked may be inserted and withdrawn from the oven, and also with one or more air-inlet devices, such as passages 9, leading through the front wall of the oven into the upper chamber 6 and pro vidcd at their front ends with lire'doors 10. One of these passages is shown on each side of the oven, a uniform distribution of heat being thereby obtained.

In case the oven is used as an inside oven these passages 9 may be used solely as air-inlets; but, if so desired, suitable heating means, such as grates, as shown at 11 in Fig. VII, or oil-burners, as shown at 111 in Fig. Vlll, may

be provided in these passages to enable the oven to be used as an outside oven.

At the roar of the oven vertical passages 12 are provided, leading in the back wall of the even from the chamber (3 to the lower pas sages 7. At the forward end of the lower passagesTare provided l'ltie-passages I3, leading forwardly and then upwardly to the stack or chiml'ley l-I, valves or dampers 15 being provided in these fines to control the draft.

16 indicates a suitable lining of iirc-ln'ick or other material for the baking-chamber. The lower passages 7 are desirably provided with holes 17 through which the soot or ashes that may be deposited in said passages maybe removed, these holes being normally closed by plugs 18.

It is in some cases desirable to provide means for supplying air to the combustion-chamber of the oven independently of the doors 8 and 11, so that said doors may be kept closed in the regular operation of the oven and more even heat thereby secured. For this purpose a trunk or passage 18 is provided across the oven below the floor or bed 5, communicating by fines or passages 19 with the main ovenchamber 6 and provided with dampers 20,

said trunk 18 opening to the outer air externally of the oven.

The operation is as follows: Assuming the oven is to be used as an inside oven, the fire is built on the bed 5 of the oven, the fuel being inserted through the main door 8 and the tire being started with dampers wide open, so as to give maximum draft. The course of the air and products of combustion will be as indicated by the arrows in Figs. II and III and IV namely, from the respective grates backwardly and upwardly against the crown of the roof and inwardly toward the center, converging at about the center of the back wall of the furnace, then downward ly through the passages 12 to the rear end of the lower passages 7, then forwardly in said lower passages beneath the oven-floor 5, then upwardly through the fines 13 to the chimney.

Passing in this manner the flame and hot gases first heat the crown, sides, and back of the oven proper and then in passing through the lower passages 7 heat the floor 5 to substantially the same temperature as the crown or top of the oven. hen the oven has been sufliciently heated in this manner, the fires are drawn and the loaves or other material inthan usual, and owing to the fact that a large part of the heat namely, that supplied in passages 7 is derived from the hot products of combustion that ordinarily pass directly up the chimney the baking may be effected with considerably less fuel than is usually required.

In using the invention as an outside oven, suitable grates 11 or oil or gas burners 111 being provided in the passages 9, as shown in Fig. VIII, the lire or flame is started at the grate or burner, as the case may be, with dam pers open, as above described, and is maintained until the entire oven has been sufficiently heated, the operation being the same as above described except that the fire or heating means is applied in passages 9 instead of in the main oven-chamber itself.

Vhat I claim, and desire to secure by Let'- ters Patent of the United States, is

A bake-oven comprising a chamber having a door in its forward end, inwardly and rearwardly directed air-inlet passages at each side of said door, heating means in said air-inlet passages. fresh-air passages entering the said chamber between the door and the air-inlet passages on each side, return-passages leading from the other end of the said chamber forwardly beneath the oven-bed, and outletflues communicating with said return-passages.

In testimony whereof I have signed my name to this specificatiomin the presence of two sul scribing Witnesses, at Los Angeles, in the county of IJOS Angeles and State of California, this 6th day of October, 1903.

- ALPHONSO EDWVARDS.

Witnesses:

GEORGE T. HACKLEY, FREDERICK S. LYON. 

